The present invention relates to paper handling, such as the feeding, aligning, slitting, and/or stacking of sheets of paper or the like and, in particular, to paper slitters in which such functions are performed.
Paper slitters are employed in various applications for cutting sheets of paper into smaller segments. For example, items such as business cards are typically produced by forming a plurality of indicia patterns on a sheet of relatively stiff paper (as by printing, thermography, etc.), and then slitting the sheet into segments, each segment containing one or more of the indicia patterns. Further slitting may thereafter be performed to cut the segments down to the individual indicia patterns.
Slitting has been heretofore performed by automated machinery which (i) receives a stack of sheets, (ii) feeds the sheets one-at-a-time to an aligning section where the sheets are properly oriented, (iii) cuts the aligned sheets into segments, (iv) fans-out the slit segments, and (v) overlaps or "shingles" the cut segments for convenient manual gathering or stacking.
A slitter machine of this type has heretofore been manufactured and sold by the Gibson Machine Manufacturing Co. of Brooklyn, N.Y. (see also U.S. Pat. Nos. 2,155,895 and 2,219,892 issued to G. A. Gibson, Jr. on Apr. 25, 1939 and Oct. 29, 1940, respectively, which disclose sheet-feeding mechanisms suitable for use on such a slitter).
The aligning of the sheets prior to being slit can be performed by abutting the sheets against an adjustable guide surface as the sheets are being advanced by a driven belt. However, performing an adjustment of the guide surface to change the sheet orientation has heretofore been slow and tedious, resulting in overly long shut-down periods.
The cutting of the sheets has heretofore been performed by means of cooperating upper and lower cutter rolls which cut the sheets into segments, and trim the side edges of the sheets. Each roll may include a circular cutting edge arranged such that cooperating upper and lower cutting edges overlap radially to cut in a scissor-like manner (e.g., see the rotary cutters of British Pat. No. 761,607 published Nov. 14, 1956). One of the opposing rolls may be provided with resilient O-rings which bear against the other roll. The rolls are fixedly mounted on parallel shafts and are relatively immovable in the axial directions during a cutting operation. It is intended that the rolls cut through the sheets in one-at-a-time fashion. On occasion, however, it may occur inadvertently that a plurality of sheets are fed simultaneously to the cutter. In such a case, jamming of the machine may occur, due to the inability of the rolls to accommodate a plurality of sheets.
Conveying of the cut segments in a divergent or fanned-out pattern is desirable in order to prevent the segments from becomming laterally overlapped and thereby interfering with proper collection of the segments in shingled rows or stacks at a downstream collection station. Heretofore, fanning-out has been achieved by means of diverging conveyor belts upon which the segments ride while being held down by a row of hold-down rolls, similar to the manner of conveyance at the aligning station. This type of conveying assembly involves numerous parts which add significantly to the expense of constructing and maintaining the machine. It is possible to eliminate the need for fanning-out of the segments by cutting-out scrap strips between adjacent segments during the splitting step. This creates a space between adjoining segments which prevents the occurrence of lateral overlap. However, such an operation results in an excessive waste of paper.
During operation of a slitter, it may be desirable to interrupt the in-feed of sheets while continuing the other functions. Clutches heretofore employed for achieving this have been complicated and unsatisfactory, and can be actuated only from one location.
It is, therefore, an object of the present invention to provide a novel paper slitting machine.
A further object is to provide such a machine which is relatively uncomplicated and well-suited to the high-speed feeding and cutting of paper sheets.
A further object is to provide an indexing mechanism for accurately aligning the sheets in a fast and simple manner.
Yet another object is to enable roller-type cutters to accommodate the simultaneous passage of more than one sheet.
Another object is to provide an inexpensive segment conveying mechanism which is relatively uncomplicated and suited to high-speed operations.
A further object is to provide a simplified clutching mechanism which enables the in-feeding of sheets to be interrupted from different locations at the machine.